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Updated: Dec 20, 2025
Author Spotlight: Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
An enhanced polarization mechanism for the metal cations modified amorphous TiO2 based electrorheological materials
Qing Wu1, Bin Yuan Zhao, Chen Fang
1State Key Laboratory of Metal Matrix Composites, Shanghai Jiaotong University, 200030, Shanghai, PRC. oicqing@yahoo.com
Abstract:
In the present work, we developed a new kind of electrorheological (ER) materials, metal cations modified amorphous TiO(2) gels. The static yield stress of Sn(4+) modified amorphous TiO(2) gel based ER fluid with a volume fraction Phi = 38% reaches 26.2 kPa at E = 3.5 kV/mm. The result shows that metal cations can significantly enhance the ER activity of amorphous TiO(2) gels. We then proposed a novel ER effect mechanism (metal cations enhanced polarization mechanism) to clarify the experimental results. We believe that it is the metal cations that enhanced the polarization of the polar groups (-OH) which results in the corresponding enhancement of the interfacial polarization.
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